According to JoyStiq (linked above), Fat Princess: Fistful of Cake for PSP will feature 50 percent more content than it's PSN counterpart.
Included are new modes where the class switching hat generators are busted from the off; meaning you'll need to collect some resources to repair them.
Another mode will also see the removal of the princess. In her place - bombs. Yes, you'll need to work as a team to bomb the castle.
To quote: "So, we of course asked for more details and learned that the game will have a variety of modes not found in the PS3 release, including one where the class hat generators are busted at the beginning of the match and must be repaired using resources before they can be used.
Another mode removes the princess from the equation and has players delivering something to their opponents' castle rather than removing it - a bomb. Sony calls this portable version of the game "Fat Princess 1.5," saying that it also has an expanded single-player component, a new map and the aforementioned new modes (plus some)."
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